[Openbts-discuss] [PATCH 1/3] uhd: Move timestamp calculations to use UHD API

[Tom T. <tom...@et...>]

Update to minimally use the UHD driver 003.005.004 API version and set
base version requirement. In effect, this uses internal UHD timestamp
conversion calls and makes stream operations dependent on the stream
instead of the base device.

Signed-off-by: Tom Tsou <tom...@et...>
---
 Transceiver52M/UHDDevice.cpp | 38 ++++++++++----------------------------
 configure.ac                 |  2 +-
 2 files changed, 11 insertions(+), 29 deletions(-)

diff --git a/Transceiver52M/UHDDevice.cpp b/Transceiver52M/UHDDevice.cpp
index f24a5f3..fe99e6e 100644
--- a/Transceiver52M/UHDDevice.cpp
+++ b/Transceiver52M/UHDDevice.cpp
@@ -125,27 +125,9 @@ static double select_rate(uhd_dev_type type, int sps)
 	return -9999.99;
 }
 
-/** Timestamp conversion
-    @param timestamp a UHD or OpenBTS timestamp
-    @param rate sample rate
-    @return the converted timestamp
-*/
-uhd::time_spec_t convert_time(TIMESTAMP ticks, double rate)
-{
-	double secs = (double) ticks / rate;
-	return uhd::time_spec_t(secs);
-}
-
-TIMESTAMP convert_time(uhd::time_spec_t ts, double rate)
-{
-	TIMESTAMP ticks = ts.get_full_secs() * rate;
-	return ts.get_tick_count(rate) + ticks;
-}
-
 /*
     Sample Buffer - Allows reading and writing of timed samples using OpenBTS
-                    or UHD style timestamps. Time conversions are handled
-                    internally or accessable through the static convert calls.
+                    or UHD style timestamps.
 */
 class smpl_buf {
 public:
@@ -630,7 +612,7 @@ bool uhd_device::flush_recv(size_t num_pkts)
 void uhd_device::restart(uhd::time_spec_t ts)
 {
 	uhd::stream_cmd_t cmd = uhd::stream_cmd_t::STREAM_MODE_STOP_CONTINUOUS;
-	usrp_dev->issue_stream_cmd(cmd);
+	rx_stream->issue_stream_cmd(cmd);
 
 	flush_recv(50);
 
@@ -639,7 +621,7 @@ void uhd_device::restart(uhd::time_spec_t ts)
 
 	cmd = uhd::stream_cmd_t::STREAM_MODE_START_CONTINUOUS;
 	cmd.stream_now = true;
-	usrp_dev->issue_stream_cmd(cmd);
+	rx_stream->issue_stream_cmd(cmd);
 }
 
 bool uhd_device::start()
@@ -745,7 +727,7 @@ int uhd_device::readSamples(short *buf, int len, bool *overrun,
 	// Shift read time with respect to transmit clock
 	timestamp += ts_offset;
 
-	ts = convert_time(timestamp, rx_rate);
+	ts = uhd::time_spec_t::from_ticks(timestamp, rx_rate);
 	LOG(DEBUG) << "Requested timestamp = " << ts.get_real_secs();
 
 	// Check that timestamp is valid
@@ -814,7 +796,7 @@ int uhd_device::writeSamples(short *buf, int len, bool *underrun,
 	metadata.has_time_spec = true;
 	metadata.start_of_burst = false;
 	metadata.end_of_burst = false;
-	metadata.time_spec = convert_time(timestamp, tx_rate);
+	metadata.time_spec = uhd::time_spec_t::from_ticks(timestamp, tx_rate);
 
 	*underrun = false;
 
@@ -881,7 +863,7 @@ bool uhd_device::setRxFreq(double wFreq)
 bool uhd_device::recv_async_msg()
 {
 	uhd::async_metadata_t md;
-	if (!usrp_dev->get_device()->recv_async_msg(md))
+	if (!tx_stream->recv_async_msg(md))
 		return false;
 
 	// Assume that any error requires resynchronization
@@ -985,9 +967,9 @@ ssize_t smpl_buf::avail_smpls(TIMESTAMP timestamp) const
 		return time_end - timestamp;
 }
 
-ssize_t smpl_buf::avail_smpls(uhd::time_spec_t timespec) const
+ssize_t smpl_buf::avail_smpls(uhd::time_spec_t ts) const
 {
-	return avail_smpls(convert_time(timespec, clk_rt));
+	return avail_smpls(ts.to_ticks(clk_rt));
 }
 
 ssize_t smpl_buf::read(void *buf, size_t len, TIMESTAMP timestamp)
@@ -1033,7 +1015,7 @@ ssize_t smpl_buf::read(void *buf, size_t len, TIMESTAMP timestamp)
 
 ssize_t smpl_buf::read(void *buf, size_t len, uhd::time_spec_t ts)
 {
-	return read(buf, len, convert_time(ts, clk_rt));
+	return read(buf, len, ts.to_ticks(clk_rt));
 }
 
 ssize_t smpl_buf::write(void *buf, size_t len, TIMESTAMP timestamp)
@@ -1074,7 +1056,7 @@ ssize_t smpl_buf::write(void *buf, size_t len, TIMESTAMP timestamp)
 
 ssize_t smpl_buf::write(void *buf, size_t len, uhd::time_spec_t ts)
 {
-	return write(buf, len, convert_time(ts, clk_rt));
+	return write(buf, len, ts.to_ticks(clk_rt));
 }
 
 std::string smpl_buf::str_status() const
diff --git a/configure.ac b/configure.ac
index 417c8e3..c967c3a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -88,7 +88,7 @@ AS_IF([test "x$with_usrp1" = "xyes"], [
 ])
 
 AS_IF([test "x$with_uhd" = "xyes"],[
-    PKG_CHECK_MODULES(UHD, uhd >= 003.004.000)
+    PKG_CHECK_MODULES(UHD, uhd >= 003.005.004)
     AC_DEFINE(USE_UHD, 1, Define to 1 if using UHD)
     AX_EXT
 ])
-- 
1.9.1